diff --git a/openstack/identity/v3/endpoints/results.go b/openstack/identity/v3/endpoints/results.go
index 7c20b8c..09e58e5 100644
--- a/openstack/identity/v3/endpoints/results.go
+++ b/openstack/identity/v3/endpoints/results.go
@@ -1,7 +1,6 @@
 package endpoints
 
 import (
-	"github.com/mitchellh/mapstructure"
 	"github.com/gophercloud/gophercloud"
 	"github.com/gophercloud/gophercloud/pagination"
 )
@@ -13,17 +12,11 @@
 // Extract interprets a GetResult, CreateResult or UpdateResult as a concrete Endpoint.
 // An error is returned if the original call or the extraction failed.
 func (r commonResult) Extract() (*Endpoint, error) {
-	if r.Err != nil {
-		return nil, r.Err
+	var s struct {
+		Endpoint *Endpoint `json:"endpoint"`
 	}
-
-	var res struct {
-		Endpoint `json:"endpoint"`
-	}
-
-	err := mapstructure.Decode(r.Body, &res)
-
-	return &res.Endpoint, err
+	err := r.ExtractInto(&s)
+	return s.Endpoint, err
 }
 
 // CreateResult is the deferred result of a Create call.
@@ -48,12 +41,12 @@
 
 // Endpoint describes the entry point for another service's API.
 type Endpoint struct {
-	ID           string                   `mapstructure:"id" json:"id"`
-	Availability gophercloud.Availability `mapstructure:"interface" json:"interface"`
-	Name         string                   `mapstructure:"name" json:"name"`
-	Region       string                   `mapstructure:"region" json:"region"`
-	ServiceID    string                   `mapstructure:"service_id" json:"service_id"`
-	URL          string                   `mapstructure:"url" json:"url"`
+	ID           string                   `json:"id"`
+	Availability gophercloud.Availability `json:"interface"`
+	Name         string                   `json:"name"`
+	Region       string                   `json:"region"`
+	ServiceID    string                   `json:"service_id"`
+	URL          string                   `json:"url"`
 }
 
 // EndpointPage is a single page of Endpoint results.
@@ -64,19 +57,15 @@
 // IsEmpty returns true if no Endpoints were returned.
 func (p EndpointPage) IsEmpty() (bool, error) {
 	es, err := ExtractEndpoints(p)
-	if err != nil {
-		return true, err
-	}
-	return len(es) == 0, nil
+	return len(es) == 0, err
 }
 
 // ExtractEndpoints extracts an Endpoint slice from a Page.
 func ExtractEndpoints(page pagination.Page) ([]Endpoint, error) {
-	var response struct {
-		Endpoints []Endpoint `mapstructure:"endpoints"`
+	r := page.(EndpointPage)
+	var s struct {
+		Endpoints []Endpoint `json:"endpoints"`
 	}
-
-	err := mapstructure.Decode(page.(EndpointPage).Body, &response)
-
-	return response.Endpoints, err
+	err := r.ExtractInto(&s)
+	return s.Endpoints, err
 }
diff --git a/openstack/identity/v3/roles/results.go b/openstack/identity/v3/roles/results.go
index 75549d3..86f21a0 100644
--- a/openstack/identity/v3/roles/results.go
+++ b/openstack/identity/v3/roles/results.go
@@ -1,10 +1,6 @@
 package roles
 
-import (
-	"github.com/gophercloud/gophercloud/pagination"
-
-	"github.com/mitchellh/mapstructure"
-)
+import "github.com/gophercloud/gophercloud/pagination"
 
 // RoleAssignment is the result of a role assignments query.
 type RoleAssignment struct {
@@ -20,7 +16,7 @@
 
 type Scope struct {
 	Domain  Domain  `json:"domain,omitempty"`
-	Project Project `json:"domain,omitempty"`
+	Project Project `json:"project,omitempty"`
 }
 
 type Domain struct {
@@ -47,35 +43,26 @@
 // IsEmpty returns true if the page contains no results.
 func (p RoleAssignmentsPage) IsEmpty() (bool, error) {
 	roleAssignments, err := ExtractRoleAssignments(p)
-	if err != nil {
-		return true, err
-	}
-	return len(roleAssignments) == 0, nil
+	return len(roleAssignments) == 0, err
 }
 
 // NextPageURL uses the response's embedded link reference to navigate to the next page of results.
 func (page RoleAssignmentsPage) NextPageURL() (string, error) {
-	type resp struct {
+	var s struct {
 		Links struct {
-			Next string `mapstructure:"next"`
-		} `mapstructure:"links"`
+			Next string `json:"next"`
+		} `json:"links"`
 	}
-
-	var r resp
-	err := mapstructure.Decode(page.Body, &r)
-	if err != nil {
-		return "", err
-	}
-
-	return r.Links.Next, nil
+	err := page.ExtractInto(&s)
+	return s.Links.Next, err
 }
 
 // ExtractRoleAssignments extracts a slice of RoleAssignments from a Collection acquired from List.
 func ExtractRoleAssignments(page pagination.Page) ([]RoleAssignment, error) {
-	var response struct {
-		RoleAssignments []RoleAssignment `mapstructure:"role_assignments"`
+	r := page.(RoleAssignmentsPage)
+	var s struct {
+		RoleAssignments []RoleAssignment `json:"role_assignments"`
 	}
-
-	err := mapstructure.Decode(page.(RoleAssignmentsPage).Body, &response)
-	return response.RoleAssignments, err
+	err := r.ExtractInto(&s)
+	return s.RoleAssignments, err
 }
diff --git a/openstack/identity/v3/services/results.go b/openstack/identity/v3/services/results.go
index c55ee62..45040c6 100644
--- a/openstack/identity/v3/services/results.go
+++ b/openstack/identity/v3/services/results.go
@@ -3,8 +3,6 @@
 import (
 	"github.com/gophercloud/gophercloud"
 	"github.com/gophercloud/gophercloud/pagination"
-
-	"github.com/mitchellh/mapstructure"
 )
 
 type commonResult struct {
@@ -14,17 +12,11 @@
 // Extract interprets a GetResult, CreateResult or UpdateResult as a concrete Service.
 // An error is returned if the original call or the extraction failed.
 func (r commonResult) Extract() (*Service, error) {
-	if r.Err != nil {
-		return nil, r.Err
+	var s struct {
+		Service *Service `json:"service"`
 	}
-
-	var res struct {
-		Service `json:"service"`
-	}
-
-	err := mapstructure.Decode(r.Body, &res)
-
-	return &res.Service, err
+	err := r.ExtractInto(&s)
+	return s.Service, err
 }
 
 // CreateResult is the deferred result of a Create call.
@@ -63,18 +55,15 @@
 // IsEmpty returns true if the page contains no results.
 func (p ServicePage) IsEmpty() (bool, error) {
 	services, err := ExtractServices(p)
-	if err != nil {
-		return true, err
-	}
-	return len(services) == 0, nil
+	return len(services) == 0, err
 }
 
 // ExtractServices extracts a slice of Services from a Collection acquired from List.
 func ExtractServices(page pagination.Page) ([]Service, error) {
-	var response struct {
-		Services []Service `mapstructure:"services"`
+	r := page.(ServicePage)
+	var s struct {
+		Services []Service `json:"services"`
 	}
-
-	err := mapstructure.Decode(page.(ServicePage).Body, &response)
-	return response.Services, err
+	err := r.ExtractInto(&s)
+	return s.Services, err
 }
diff --git a/openstack/identity/v3/tokens/results.go b/openstack/identity/v3/tokens/results.go
index ec98c1c..7dd2c0b 100644
--- a/openstack/identity/v3/tokens/results.go
+++ b/openstack/identity/v3/tokens/results.go
@@ -3,7 +3,6 @@
 import (
 	"time"
 
-	"github.com/mitchellh/mapstructure"
 	"github.com/gophercloud/gophercloud"
 )
 
@@ -12,10 +11,10 @@
 // If supported, it contains a region specifier, again if provided.
 // The significance of the Region field will depend upon your provider.
 type Endpoint struct {
-	ID        string `mapstructure:"id"`
-	Region    string `mapstructure:"region"`
-	Interface string `mapstructure:"interface"`
-	URL       string `mapstructure:"url"`
+	ID        string `json:"id"`
+	Region    string `json:"region"`
+	Interface string `json:"interface"`
+	URL       string `json:"url"`
 }
 
 // CatalogEntry provides a type-safe interface to an Identity API V3 service catalog listing.
@@ -27,18 +26,18 @@
 type CatalogEntry struct {
 
 	// Service ID
-	ID string `mapstructure:"id"`
+	ID string `json:"id"`
 
 	// Name will contain the provider-specified name for the service.
-	Name string `mapstructure:"name"`
+	Name string `json:"name"`
 
 	// Type will contain a type string if OpenStack defines a type for the service.
 	// Otherwise, for provider-specific services, the provider may assign their own type strings.
-	Type string `mapstructure:"type"`
+	Type string `json:"type"`
 
 	// Endpoints will let the caller iterate over all the different endpoints that may exist for
 	// the service.
-	Endpoints []Endpoint `mapstructure:"endpoints"`
+	Endpoints []Endpoint `json:"endpoints"`
 }
 
 // ServiceCatalog provides a view into the service catalog from a previous, successful authentication.
@@ -59,14 +58,10 @@
 
 // ExtractToken interprets a commonResult as a Token.
 func (r commonResult) ExtractToken() (*Token, error) {
-	if r.Err != nil {
-		return nil, r.Err
-	}
-
-	var response struct {
+	var s struct {
 		Token struct {
-			ExpiresAt string `mapstructure:"expires_at"`
-		} `mapstructure:"token"`
+			ExpiresAt string `json:"expires_at"`
+		} `json:"token"`
 	}
 
 	var token Token
@@ -74,35 +69,26 @@
 	// Parse the token itself from the stored headers.
 	token.ID = r.Header.Get("X-Subject-Token")
 
-	err := mapstructure.Decode(r.Body, &response)
+	err := r.ExtractInto(&s)
 	if err != nil {
 		return nil, err
 	}
 
 	// Attempt to parse the timestamp.
-	token.ExpiresAt, err = time.Parse(gophercloud.RFC3339Milli, response.Token.ExpiresAt)
+	token.ExpiresAt, err = time.Parse(gophercloud.RFC3339Milli, s.Token.ExpiresAt)
 
 	return &token, err
 }
 
 // ExtractServiceCatalog returns the ServiceCatalog that was generated along with the user's Token.
-func (result CreateResult) ExtractServiceCatalog() (*ServiceCatalog, error) {
-	if result.Err != nil {
-		return nil, result.Err
-	}
-
-	var response struct {
+func (r CreateResult) ExtractServiceCatalog() (*ServiceCatalog, error) {
+	var s struct {
 		Token struct {
-			Entries []CatalogEntry `mapstructure:"catalog"`
-		} `mapstructure:"token"`
+			Entries []CatalogEntry `json:"catalog"`
+		} `json:"token"`
 	}
-
-	err := mapstructure.Decode(result.Body, &response)
-	if err != nil {
-		return nil, err
-	}
-
-	return &ServiceCatalog{Entries: response.Token.Entries}, nil
+	err := r.ExtractInto(&s)
+	return &ServiceCatalog{Entries: s.Token.Entries}, err
 }
 
 // CreateResult defers the interpretation of a created token.